You will need

- calculator, the value of the number π = 3,14 , the value of the radius r and Central angle α taken from the conditions of the problem.

Instruction

1

First you need to decide the main concepts. A circle is the set of all points plane that are at a given positive distance from some given point of the plane, called the center

**of the circle**(point O). Arc - part of**circumference is**located between two points A and b of this**circle**, where OA and OV radii of this**circle**. To distinguish between these**arcs**, each of them mark an intermediate point L and M. Thus, we obtain two**arcs**ALB and AMB.2

The arc

?, and if more straight angle, 360° - ?.

**of the circle**determined by a Central angle ?. Angle with vertex in the center**of the circle**is called its Central angle. If the Central angle is less than straight angle, then its degree measure is equal?, and if more straight angle, 360° - ?.

3

So, the arc

L = ?r?/180

where ? is a numeric constant equal 3,14.

Substituting in the formula values ?, r ? and using a calculator you can easily calculate

**of the circle**defined by the radius**of the circle**r and Central angle ?. Knowing these two values, it is easy to calculate*the length***of the arc**L by the formula:L = ?r?/180

where ? is a numeric constant equal 3,14.

Substituting in the formula values ?, r ? and using a calculator you can easily calculate

*the length***of the arc**L.